The present invention relates generally to field of mobile devices, and more particularly to mobile devices that can manipulate content being presented on a user-interface display via activated user-input elements.
Mobile devices, including personal digital assistants (PDAs), handsets, and other computing devices, often rely on keys located on the surface of the device to receive user-initiated inputs. Typically an input is made by selecting a single-purpose key that is effective for a specific operation, regardless of the application being presently implemented. Although these single-purpose keys (e.g., directional keys, and “enter” key) are adapted to perform their respective specific operations on many applications, there are increasingly more varieties of applications that may be executed on a mobile device. These disparate applications perform operations that are often triggered by uncommon types of inputs (e.g., rotate image, collapse window, etc.). Accordingly, the limited surface area available on a mobile device to house single-purpose keys would be required to grow exponentially to accommodate these inputs of the various applications. However, mobile devices having large space consumption, in many cases, are not practical in the compact mobile environment. Additionally, new applications having different operations than those supported by a mobile device presently in the market would create frustration to those who presently own a mobile device and to those companies creating new applications.
Further, offering a single-purpose key to provide a wide range of inputs is not intuitive to users manipulating content on a user-interface display. For instance, scrolling vertically through a document using left and right directional keys hinders a user from easily detecting the proper single-purpose keys to depress, and creates a disconnect between the key layout of the mobile device and the functionality of an application. Accordingly, a multifunction set of keys that can adapt to a variety of applications, and can be continually updated, would provide a robust method of facilitating user control over the functionality of a plurality of applications.